(1) Field of the Invention
This invention relates to rotary compressors, and more particularly to a rotary compressor of the type suitable for use as a compressor for compressing a refrigerant for an air conditioning system of a motor vehicle, for example.
(2) Description of the Prior Art
In rotary compressors for compressing a refrigerant, it is necessary that back pressure be applied to the vanes to prevent chattering of the vanes during operation, as is disclosed in Japanese Patent Laid-Open Nos. 10411/76 and 133811/76. However, in case the back pressure applied to the vanes is too high, a loss of power would be great and the load applied to the prime mover would be increased. Moreover, a reduction in the service life of the compressors would result.